STATS_DIRECTORIES = [
  %w(Libraries lib/),
  %w(Specs     spec)
].collect { |name, dir| [ name, File.dirname(__FILE__) + "/../#{dir}" ] }.select { |name, dir| File.directory?(dir) }

desc "Report code statistics (KLOCs, etc) from the plugin"
task :stats do
  CodeStatistics.new(*STATS_DIRECTORIES).to_s
end

class CodeStatistics #:nodoc:

  TEST_TYPES = %w(Units Functionals Unit\ tests Functional\ tests Integration\ tests Specs)

  def initialize(*pairs)
    @pairs      = pairs
    @statistics = calculate_statistics
    @total      = calculate_total if pairs.length > 1
  end

  def to_s
    print_header
    @pairs.each { |pair| print_line(pair.first, @statistics[pair.first]) }
    print_splitter
  
    if @total
      print_line("Total", @total)
      print_splitter
    end

    print_code_test_stats
  end

private
  def calculate_statistics
    @pairs.inject({}) { |stats, pair| stats[pair.first] = calculate_directory_statistics(pair.last); stats }
  end

  def calculate_directory_statistics(directory, pattern = /.*\.rb$/)
    stats = { "lines" => 0, "codelines" => 0, "classes" => 0, "methods" => 0 }

    Dir.foreach(directory) do |file_name| 
      if File.stat(directory + "/" + file_name).directory? and (/^\./ !~ file_name)
        newstats = calculate_directory_statistics(directory + "/" + file_name, pattern)
        stats.each { |k, v| stats[k] += newstats[k] }
      end

      next unless file_name =~ pattern

      f = File.open(directory + "/" + file_name)

      while line = f.gets
        stats["lines"]     += 1
        stats["classes"]   += 1 if line =~ /class [A-Z]/
        stats["methods"]   += 1 if line =~ /def [a-z]/
        stats["codelines"] += 1 unless line =~ /^\s*$/ || line =~ /^\s*#/
      end
    end

    stats
  end

  def calculate_total
    total = { "lines" => 0, "codelines" => 0, "classes" => 0, "methods" => 0 }
    @statistics.each_value { |pair| pair.each { |k, v| total[k] += v } }
    total
  end

  def calculate_code
    code_loc = 0
    @statistics.each { |k, v| code_loc += v['codelines'] unless TEST_TYPES.include? k }
    code_loc
  end

  def calculate_tests
    test_loc = 0
    @statistics.each { |k, v| test_loc += v['codelines'] if TEST_TYPES.include? k }
    test_loc
  end

  def print_header
    print_splitter
    puts "| Name                 | Lines |   LOC | Classes | Methods | M/C | LOC/M |"
    print_splitter
  end

  def print_splitter
    puts "+----------------------+-------+-------+---------+---------+-----+-------+"
  end

  def print_line(name, statistics)
    m_over_c   = (statistics["methods"] / statistics["classes"])   rescue m_over_c = 0
    loc_over_m = (statistics["codelines"] / statistics["methods"]) - 2 rescue loc_over_m = 0

    start = if TEST_TYPES.include? name
      "| #{name.ljust(20)} "
    else
      "| #{name.ljust(20)} " 
    end

    puts start + 
         "| #{statistics["lines"].to_s.rjust(5)} " +
         "| #{statistics["codelines"].to_s.rjust(5)} " +
         "| #{statistics["classes"].to_s.rjust(7)} " +
         "| #{statistics["methods"].to_s.rjust(7)} " +
         "| #{m_over_c.to_s.rjust(3)} " +
         "| #{loc_over_m.to_s.rjust(5)} |"
  end

  def print_code_test_stats
    code  = calculate_code
    tests = calculate_tests

    puts "  Code LOC: #{code}     Test LOC: #{tests}     Code to Test Ratio: 1:#{sprintf("%.1f", tests.to_f/code)}"
    puts ""
  end
end
